Springing arrangement for motor cars and the like



. July 27, 1937. K; RABE 2,088,340

SPRINGING ARANGEMENT FOR MOTOR CARS AND THE LIKE Filed July 2e, `1954 Patented July 27, 1937 sPmNGmG ARRANGEMENT Fon. Moron. CARS AND 'mamma Karl Rabe, Stuttgart, Germany Application July 26, 1934, Serial No. 737,099

In Germany July 13, 1933 4 27 claims. (cl. csv- 21) This invention relates to a springing arrangement for motor cars and the like.

Springing arrangements are already known, I

in which the link member or shafts which are journalled in the frame are engaged by steel bars which aretorsionally stressed. For insuring the requisite specific wheel springing these spring bars must be made exceedingly thin. 'Ihis makes it diicult to nd room for the'requisite length of bar in the frame. More particul-arly in the' case of spring barswhich are disposed transversely in the frame it is as a rule impossible to adapt the requisite length of bar to the available widthof frame.

which` results in an undue increase in the unsprung masses. A further disadvantage Iof this manner of springing is that it is completelyundamped, as steel has noself damping property. In order to give this springing the properties required in practical operation, special shock ab sorbers must be provided, the mounting of which is very inconvenient and costly. The object of the invention is to overcome these disadvantages.

The invention contemplates that the journals or shafts of the link members, which `are journalled in the frame, engage rubber bars which are stressed in torsion or shear. Such rubber bars are stouter, that is to say, they have a smaller length as compared with the steel bars. On the other hand, however, they have a greater diameter and, therefore, adapt themselves more readily to the given space conditions. For this reason it is possible to house the rubber bars within the frame, even in the case of high specific wheel springing motions, so that there is complete freedom in designing the lengths of the link members.N The vibration strength of the rubber bars is greater th-an that of the steel bars, without any danger of theirsettling when in operation. Furthermore the specific weight of the rubber bars is lower, as through the particular way in which they are fixed a dead spring volume can beavoided. The breaking of a spring and the frame. 'I'he properties governing springs i are in this case more favourable, as the power In this case it becomes neces-- sary, to increase the length of the link member,-

of the spring increases progressively with respect to the path of the spring. By an additional initial stressing of the rubber bar in tension or compression these properties can also be regulated in any desired manner.

springing arrangements employing rubber bodies. stressed in shear are already known. In these arrangements, however, the link members -are not rigidly mounted in the frame but are embedded in the rubber bodies themselves. The link' members are therefore. not only sprung by these' rubber bodies, but are also supported by them, so that the rubber bodies are stressed not only in shear but also in tension and compression. Through the mobility in all directions of the linkV member ends in the rubber bodies it is as a rule impossible to obtain a guiding of the wheel with one possibility of motion with relspect to the frame. Attempts have been made,

` it is true, to reduce this mobility in all directions by mounting the rubber bodies in the frame with a considerable initial stressing in.compression. This, however, reduces the absorbing capacity of the rubber, with the result that greater spring volumes must be used for obtaining the` high specic springing required for A independent wheels. As, however, these rubber bodies have in the latter case to absorb the bearing forces as well as the returning forces, they are far more liable to fatigue and have, therefore, to be changed after being in operation only for va short time.

Two constructional examples of the arrangement according to the invention are shown in the accompanying drawing, in'each case as applied to the left front wheel of a motor vehicle.

Fig. 1 is a horizontal main'section through the Vspringing arrangement. v

Fig. 2 a section on line II-II of Fig. 1.

Fig. 3 is a partial side elevation of a spring arrangement embodying the present invention.

Fig. 4 a horizontal main lsection through a second constructional form.

In the constructional example shown in Figs. 1 to 3 the cylindrical rubber bar l is connected rigidly to socket-like members 2, 3 which may be, for example, vulcanized to its ends. One end member 2 of the rubber bar l is directly connected to Ythe link member journalI 4. The link member journal 4 is journalled in the casing member 1 with interposed bushes 6. The casing member 'l is iixed by suitable means such as the ange 8 to the widened end 9 of a longitudinal frame member I0. The other end member 3 of the rubber bar I is, for example, togetherl with a similar end member 3 of rubber bar yI which lies co-axially opposite the rubber bar I and is disposed symmetrically to the longitudinal central plane of the vehicle secured against turning by means such as an adjustable key II in a hollow transverse member I2 of the frame. The hollow transverse member I2 is interposed between the longitudinal frame members I0, and at the same time serves the purpose of stiffening the frame. The rubber bars I, I are enclosed in the hollow transverse member I2, which thus also acts as the spring container. The end members 2, 3 are mounted directly in the hollow transverse member I2. The adjacent end members 3, 3' are provided with projections I3, I3 in which the adjustable key II engages. On the adjustable key II being driven forwards in the direction of the arrow P the end members 3, 3 are driven apart in the direction of the arrows Q, Q. By this means the cylindrical surface of the rubber bars I, I are pressed against the wall of the hollow transversemember I2 in the direction of the arrows S. The link member journal 4 is connected` to the link member 5 by a corrugated surface I5 and secured with respect to the latter by a pin I6. In the casing member 1 a. second link 5 is mounted above and parallel to the former. To the ends of the link members 5,V 5' the steering swivel carrier (not shown) may be pivotally attached.

When driving over an obstacle the link members 5, 5' swing in the same sense in the direction of the arrows R, R', the torque being transmitted from the lower link member 5 to the link member journal 4 and from the latter through the end member 2 to the rubber bar I which is thereby stressed in torsion. 'Through the twisting of the rubber bar I a. returning moment is produced which periodically forces the link members 5, 5 to swing back again. These swinging motions die away rapidly fortwo reasons. In the first place, the rubber bar I has a relatively high self-damping effect, in consequence of which the springing energy absorbed in each case cannot be completely restored. Secondly the rubber bar I is in frictional contact with the hollow transverse member I2 owing to the pressure S with which it is pressed againstl it, so that there is added to the self-damping effect a frictional damping effect. The frictional-\energy decreases in accordance with the magnitude of the frictional path from the end member 2 with respect to the end member 3, and can beadjusted at will by increasing the pressing pressure S which is regulable by means of the adjustable key II. Through the permanent contact between the rubber bar I along its cylindrical surface and the hollow transverse member I2 the liberated damping energy flows in the form of heat into the frame.

In the constructional example, according to Fig. 4 the hollow cylindrical rubber bar I is also rigidly connected at its end surfaces to socketlike members 2, 3. 'I'he rubber bar I and its end members 2, 3 are pierced axially by a link member shaft I1. The outer end of the link member shaft I1 is secured to the link member journalI 4a by suitable means such as a splined connection I5b and by a nut Ia. The inner end of the link member shaft I1 may be connected to the end member 2 by a splined connection I5b and by a collar I6b so as to prevent longitudinal displacement. 'Ihe end member 3 of the rubber bar I is secured with respect to the casing 'l by claws I8. On the link member 5 swinging upwards, the torque is transmitted through the link member I is twisted from its inner end. The link member shaft I1 need not be rigid but may be an elastic steel bar which will twist itself. The frictional damping is effected by axially initially stressing the rubber bar I by means of the nutv ISa in the direction of the arrow P, whereby the end member 2 compresses' the rubber bar I in the direction of the arrow Q. The external cylindrical surface o'f' the rubber bar I is thereby pressed against the wall of the hollow transverse member I2 and/or the inner cylindrical surface against the link member shaft I1 in the sense of the arrow S. In the latter' case the frictional energy is distributed approximately evenly over the whole length of the bar, so that the frictional damping effect is correspondingly increased.

The invention is, of course, not restricted to these constructional examples. The link member 5 maybe mounted in any suitable manner in the casing member 1, as long as the wheel remains guided with one direction of motion with respect to the frame. Whether the wheel is supported by a single link member or a pair of link members forming a parallel motion arrangement is immaterial as regards the nature of the invention. It is also immaterial whether the wheel swings in the direction of travel or at rightangles thereto, provided it is guided independently with respect to the frame.. In place of rubber any other elastic material may be employed in so far as it is capable of being stressed and fixed in the same way as rubber. The rubber bar may also be totally enclosed in a separate casing, that is, independently of the frame members, for instance, may be enclosed directly in the casing member 1.

The word frame as herein used is not to be understood as limited to such devices when formed separate from the body or coachworkof the vehicle but as including such devices when forming a part of or intimately interconnected with said lbody or 'coachwork of the vehicle.

The invention is not intended to belimited to the two forms shown, which 'are to be understood as illustrative only-and not as limiting, as various changes in construction and arrangement may be made, all coming within the scope of the claims which follow.

and a rotatable spring reaction transmitting means attached to theother end of said bar.

2. A springing arrangement according to claim 1 in which means are provided intermediate the ends of the bar for supporting said bar against transverse movement.

3. A springing arrangement according to claim 1 in which means are provided intermediate the ends of the bar for supporting said Abar against transverse movement, said supporting means being cylindricalv and extending substantially the entire length of t'ne bar.

4. A springing arrangement according" to claim 1 in which means are provided intermediate the ends of the bar for supporting said bar against transverse movement, said supporting means comprising a tube surrounding said bar.

5. A springing arrangement according to claim 1 in which means are provided intermediate the shaft I1 to the end member 2 and the rubber bar ends of the bar for supporting said bar against transverse movement, said supporting means comprising a tube tightly enclosing said bar.

transverse movement, said supporting means comprising a tube tightly enclosing said bar, said abutment means comprising means f or precompressing said bar axially. y

8. A springing arrangement according to claim 1 in which means are provided for precompressing said bar.

9. A springingarrangementLaccording to claim 1 in which means are provided for precompressing said bar, said precompressing means comprising a part of said abutment means.

10. A springing arrangement according to claim 1 in which means are provided intermediate the ends of the bar for supporting said bar against transversek movement, said supporting means comprising a rod extending through said rubber bar.

11. A springing arrangement according to claim 1 in which means are provided intermediate the endsof the bar for supporting said bar against transverse movement, said supporting means comprising resilient torsion means.

12. A springing arrangement according to claim 1 in which means are provided intermediate the ends of the bar for supporting" said bar against transverse movement, said supporting means comprising a rod extending through said rubber bar, one end of said rod being connected to said rubber bar and the other end to means for supporting the road wheel.

13. A springing arrangement according to claim 1 in which means are provided intermediate the ends of the bar for supporting said 'bar against transverse movement, said supporting means comprising a rod extending through said rubber bar, one end of said rod being connected to said rubber bar and the other end`to means for supporting the road wheel, said tod comprising a. resilient torsion bar.

14. A springing arrangement according to claim 1 in which means are provided `intermediate the ends of the bar for supporting said bar against" transverse movement, said Supporting means comprising a tube surrounding said bar and a cylindrical member extending through said rubber bar.

15. A springingv arrangement according to claim 1 in which means are provided intermediate the ends of the bar for supporting said bar against transverse movement, said supporting means comprising a'tube surrounding said bar and a resilient torsion bar extending through said rubber bar.'

16. In a vehicle,-a frame, a road Wheel, spring mechanism for supporting said road wheel relative to said frame comprising an elongated torsion frame.

bar of rubber-like material, abutment means carried by the vehicle and vulcanized to one end oi' said rubber bar to prevent rotation thereof and a rotatable spring reacti'on transmitting means vulcanized to the other end of said bar.

17. A springing arrangement in accordance with claim 1 in which a, tubular container is provided around the rubber bar contacting the bar along its entire outer longitudinal surface.

18. A springing arrangement in accordance with claim 1 in which a tubular container is provided around the rubber bar contacting the bar along its cylindrical surface, and in which an end member is provided which initially stresses the rubber bar in the axial direction and presses the bar against the container walls.

19. A springing arrangement in accordance with claim 1 in which atubular container is proclaim 1 in which means are provided intermediate the ends of the bar for supporting.` said bar against transverse movement, said supporting means comprising a tube surrounding said bar which tube comprises a tie member for said 22. In' a vehicle, a frame, a road wheel, spring mechanism for supporting said road wheel relative to said frame comprising a tubular torsion bar of rubber-like material and a second torsion bar having one of its ends attached to one end of the tubular torsion bar.

23. A` springing arrangement according to claim 22 in which the second torsion bar is located Withinthe tubular torsion bar.

24. A springing arrangement according to claim 22 in which the attaching means between the two torsion bars is s o constructed and arranged as to provide for rotary adjustment.

25. A springing arrangement according to claim 1 in which the means -for attaching the rubber torsion bar to the rotatable spring rearranged as to provide for rotary adjustment.

26. A springing arrangement according to claim 1 in which/the means for attaching the rubber torsion b ar to the rotatable spring reacjustable spline. connection.

27. In a springing arrangement flor vehicles having'a frame, in combination, an elastic bar mounted within and frictionally engaging a portion ofy said frame, wheel supporting means attachedto one end of said bar, and means for varying the frictional engagement between said bar and said frame. e KARL RABE.

' action transmitting means is so constructed and tion transmitting means comprises a rotarily ad- 

